This invention relates to biological cell treatment, and more particularly to evaluating the biological viability or survivability of cells.
In order to prevent the cells supplied to a microchamber from individually adhering to the surfaces of the walls of the microchambers, a hydrostatic pressure is applied intermittently (in an amount and manner similar to that of the present invention) from apertures in the bottom portions of the chambers to the interior thereof as disclosed in Japanese Patent Laid-Open No. 95768/1989 and U.S. patent application Ser. No. 07/253,560 filed October, 1988 now U.S. Pat. No. 5,154,814.
In general, the protoplast used for the cell fusion of a plant is protoplasm obtained by isolating leaf cells by enzyme treatment to remove the cell walls. As disclosed in the literature (edited by an incorporated body of the Technical Information Association of Agriculture, Forestry and Fisheries, "Research Journal", Vol. 13, No. 5, (1990-5) 3-12), fused hybrid cells are transferred onto a culture medium, and the cell walls are subjected to regeneration, cell division and callusing, the hybrid cells then growing into a plant body. The protoplast isolating condition differs according to the kind of plant, and it is said to be important to develop an optimum protoplast isolating condition under which the viability of protoplast, i.e. the capability of regenerating, dividing and multiplying the cell walls thereof, is not spoiled.
The treatment condition including optimum isolation, culture and cell fusion has been researched by trial and error repeatedly, usually by transferring protoplast pretreated with various kinds of cell wall digesting enzymes (such as pectinase and cellulase) onto a culture medium, culturing the same for several weeks, and observing the condition of the protoplast being divided and multiplied, or by cultivating this protoplast for more several months and observing whether an original plant body is regenerated or not. Such conventional determining of viability involves a technical problem that it takes at least 2-3 weeks before the viability results have been obtained. Moreover, it is necessary that the protoplast be put under an aseptic condition to be cultured for a long period of time. Consequently in determining viability, a great deal of labor is required in enzyme treatment, to make sterilization arrangements and to control the sterilization of a culture medium for a long period of time.